Do as the Monsters Do
by LadyScriba
Summary: Dark AU where the bat family are villains and David Cain is the hero. Cassandra has always known the difference between herself and her father and it brings her to the Oracle with a surprising request. Warning for murder mention and violence.


Disclaimer: I don't own any of these characters.

Author's note: A special thanks to my sister, lesprita and Esther-Channah. And you could also find this on AO3!

Once upon a time, Cassandra thought she could be a hero. She dreamed of brandishing a mask and a cape for the world to see. She imagined David's heavy hand, with its thick callus and scars, on her shoulder and smiling at her with pride. His greatest creation. His legacy. But gone were the days and nights of Cassandra working to be David's concept of justice. She broke bones, spilled blood, and severed veins for it, but her work amounted to David's frown. It takes Cassandra a long time to realize why.

His justice was not in her nature. A slim costume that didn't fit.

Here's what Cassandra also realizes before turning fourteen: she will never be her father. She lives for that exact moment before the finishing blow; how time fractures for her to revel in her broken prey before they are lifeless on the concrete floor and it doesn't matter what they did to deserve a grisly end. She is most alive when in that person's eyes there's terror and then nothing.

It brings her to the den of David's enemy, the eyes of Batman. Cassandra doesn't look away from Barbara Gordon, not even after a stretch of silence that is too long to be comfortable. She's not sure what she expected the Oracle to look like: but certainly not the woman in a wheelchair, exposed to any attack at the front of her desk. Barbara is vulnerable and yet…instinct demands Cassandra to maintain distance from her. She leans against the wall across the room with her hoodie over her head and arms crossed. After weeks of searching, she at last finds Oracle, though the Clocktower looks more like an attic than an actual base of operations.

Barbara returns her stare with one so sharp it could draw blood. Cassandra starts to expect a fight and finds solace in the knives in her sleeves. Eventually, Barbara leans back and her cutting eyes closes briefly in favor of peace. "I'm going to come clean with you," she says finally, her words a confession. Her manicured nails, razor-edged and neat, starts tapping in a measured beat. "Bringing you in is a risk."

Cassandra frowns. Barbara clarifies. "I'm not the one you should worry about. It's Batman's test. He has a particular method of making sure his allies remain… his allies."

Barbara allows Cassandra to see only her annoyance, as if Batman's criteria is a nuisance. She props up an elbow to rest her chin on her palm. "I keep telling him that you belong here, but with him, there can never be exceptions to procedure." She pauses, thoughtful.

"Do you know his first rule of thumb?"

It's the first question Barbara's asked of her all night and it shames Cassandra to shake her head.

Barbara's eyes become trimmed stone then, sharp and hard. "Without order, the system falls apart."

Cassandra didn't expect the woman in a wheelchair to be Batman's eyes but she also never expected the beauty—of the whispers of cruelty along her skin. Barbara is almost ivory marble, handmade in vicious elegance. Cassandra says nothing in her study of Oracle.

The morning light radiates from the window and reflects off of Barbara's glasses. The challenge is hidden in her next words, "It's not too late to turn back now. You can leave—no one has to know you were here."

Lies.

The one true gift David gave to Cassandra was the ability to see lies, to pull the thread and undo the elaborate patterns. She could see the words for what they are. She remembers David's file on Oracle—the trail of bodies that litter the street like fingerprints on a smooth surface. Sometimes, the bodies are never found and all that remains are plastered pictures on milk cartons.

David always took these cold cases to heart: the blue veins visible on his temple, his eyes so full of rage. But this is what she vividly remembers: his perfect, clear eyes unfocused and his hands in a strangled fist and the violence it promised and, and—the tremors that ran along her arms and the only time love is applicable to her tongue. Batman and his tribe were the only people on Earth that made David like her.

The test is just as clear: if she leaves, it's a death sentence. This seemingly vulnerable woman before her can erase her existence within a week.

That's fine. It was never her intention to leave without getting what she wants. Even if Batman must find his beautiful Oracle with a knife between her eyes, she will earn her stay.

Cassandra gives her an even look. "Make me Batgirl," she says.

The words are so simple, yet Barbara sees the threat in Cassandra's eyes; it's a flicker behind her irises that the Oracle recognizes. Her lips curl in a smile. "Tell me about your dad."

Cassandra is not her father. Once upon a time, she tried to be. The cape, heavy on her shoulders, and being what her father wanted. But for the first time since she left David's side, the ghost of the girl in a mask and cape is put to rest. She finds the identity of Batgirl a better fit for clothing than anything her father would've had to give. In a den full of monsters, she no longer has to pretend to be something she's not.


End file.
